I find that most often the people who openly declare their convictions in some form of religion (religion taken in the widest sense - encompassing Christianity, Islam, Judaism, or other 'religious' religions, Socialism, Anti-Socialism, Conservatism or other political religions, and sundry other kinds of 'religion') are the ones who are most inclined to try to force their surrounding to share their belief often.
Loud, public declarations of belief, like "have you met...?", "... is scum/filth/<insert other term>, and should be...", "Perl sucks" etc, make me want run away as far and fast as possible.

Of course there are notable exceptions, ie the beliefs I share: that Monty Python is funny, that 42 is the answer, etc.